Walckenaeria dahaituoensis, Song & Li & P. & R., 2011

Song, Yanjing & Li, Shuqiang, 2011, Notes on Walckenaeria species (Araneae: Linyphiidae) from China, Revue suisse de Zoologie 118 (1), pp. 175-196 : 180-184

Walckenaeria dahaituoensis sp. n.

Figs 3-5

HOLOTYPE: IZCAS, without registration number; ♂; China, Hebei Province, Zhangjiakou City, Chicheng County, Dahaituo National Nature Reserve (40.90ºN 115.83ºE); collected by Q. Wang, Y. Song and G. Zheng; collected on 5.11.2005.

PARATYPES: IZCAS (3♂ 5♀) and MHNG (2♀ 2♂), without registration number; same data as for holotype . – IZCAS, without registration number; 3♂; China, Beijing, Mentougou District, Xiaolongmen Forest Park , alt. 1225m; collected by X. Yu; collected on 21.09.1999 .

DIAGNOSIS: The new species is similar to W. chiyokoae and W. asymmetrica sp.n., but can be distinguished from these two species by the additional rows of hairs at the base of the lateral eyes in males ( Fig. 4A ), the shape of the male palpal tibial apophyses ( Fig. 3E ), the strongly curved, distally pointed tailpiece of the embolic division ( Fig. 3A ), the equally broad lip-shaped extension of the dorsal plate of the epigynum ( Fig. 4D ) and the different course of the copulatory ducts in posterior view ( Fig. 4G ). The vulva system is very similar to that of W. chiyokoae and W. asymmetrica , and females can only be safely identified when collected together with males.

DESCRIPTION OF HOLOTYPE: Total length 2.54. Carapace 1.38 long, 0.86 wide, orange-brown. Head elevated into a very large lobe carrying posterior median eyes; a shallow sulcus running back from behind PLE and containing a small pit anteriorly; 5 long hairs arranged in a line at each base of lateral eye ( Fig. 4A, B ). Clypeus 0.31 high, slightly swollen and with a patch of weak hairs in the center ( Fig. 4A ). AME diameter 0.05, ALE 0.07, PME 0.08, PLE 0.08, AME interdistance 0.63 times their diameter, AME-ALE interdistance 1.73 times ALE diameter, PME interdistance 3.08 times their diameter, PME-PLE interdistance 3.08 times PLE diameter. Sternum 0.71 long, 0.64 wide. Coxa IV interdistance 1.06 times their width. Chelicera chestnut-brown, with 4 promarginal and 4 retromarginal teeth. Tibia of leg I 8.60 times longer than deep. Tm I 0.59, Tm IV present. Tibiae of all legs with very short spines, one third of width of tibiae. Number of dorsal spines on tibiae of legs I-IV: 1-1-1-1. Leg measurements: I 4.09 (1.14, 0.33, 1.08, 0.95, 0.59); II 3.99 (1.11, 0.33, 1.05, 0.93, 0.59); III 3.31 (0.94, 0.30, 0.81, 0.77, 0.49); IV 4.26 (1.16, 0.31, 1.14, 1.08, 0.57).

Palp: Patella slightly shorter than femur ( Fig. 3D ). Tibia short, armed with 1 stout retrolateral apophysis and 1 large biforked prolateral apophysis, the latter composed of 1 long broad branch and 1 strongly sclerotized needle-like branch; with 1 prolateral and 2 retrolateral trichobothria ( Fig. 3E ). Paracymbium C-shaped, slightly hooked, with 3 hairs on the basal arm near its junction with the cymbium ( Fig. 3C ). Tegulum distal to subtegulum in unexpanded palp ( Fig. 3F ). Protegulum without papillae ( Fig. 3A, B ). Distal suprategular apophysis similar to that of W. chiyokoae but without small tooth on upper margin of groove ( Fig. 3F ). Column rounded, totally visible in prolateral view ( Fig. 3A ). Embolic division ( Fig. 4E, F ) similar to that of the two above mentioned species, but tailpiece pointed and strongly curved downwards ( Fig. 3A ).

DESCRIPTION OF FEMALE PARATYPE (from type locality): Carapace ( Fig. 4C ) unmodified, similar to that of male in coloration. Total length 2.20. Carapace 1.08 long, 0.80 wide. Clypeus 0.23 high. AME diameter 0.06, ALE 0.09, PME 0.08, PLE 0.08, AME interdistance 0.44 times their diameter, AME-ALE interdistance 0.47 times ALE diameter, PME interdistance 1.08 times their diameter, PME-PLE interdistance 0.77 times PLE diameter. Sternum 0.72 long, 0.64 wide. Coxa IV interdistance 1.13 times their width. Chelicera with 4 promarginal and 2 retromarginal teeth. Tibia of leg I 7.27 times longer than deep. Tm I 0.61, Tm IV present. Spines on tibiae of all legs as long as width of tibiae. Number of dorsal spines on tibiae of legs I-IV: 1-1-1-1. Leg measurements: I 3.83 (1.13, 0.34, 1.00, 0.84, 0.52); II 3.68 (1.08, 0.34, 0.94, 0.82, 0.51); III 3.22 (0.93, 0.30, 0.79, 0.75, 0.46); IV 4.09 (1.14, 0.30, 1.12, 1.01, 0.53).

Surface of epigynum almost transparent. Doral plate with evenly broad lipshaped extension totally exposed in ventral view ( Fig. 4D ). Vulva system ( Fig. 5A, B ) similar to that of W. chiyokoae and W. asymmetrica sp. n.

ETYMOLOGY: The specific name is taken from the type locality.

VARIATION: 7♀ and 6♂ were measured. The total length varies from 2.58 to 2.64 in males, 2.20 to 2.33 in females. The carapace length is 1.38 to 1.42 in males, 1.08 to 1.22 in females; width 0.86 to 0.88 in males, 0.80 to 0.89 in females. The species shows considerable intraspecific variation in the shape of the anterior part of the vulva ( Fig. 5A, C, D ).

DISTRIBUTION: Only known from Baotianman Nature Reserve in Henan Province, China.

HABITAT: The spiders were found in the leaf litter of a birch forest.

Figures

FIG. 3 Walckenaeria dahaituoensis sp. n.; male holotype. (A) Distal part of left palp, prolateral view. (B) Same, ventral view. (C) Paracymbium, ventral view. (D) Patella and femur of left palp, retrolateral view. (E) Tibia of left palp, dorsal view. (F) Distal part of left palp, retrolateral view. Scale lines: 0.1 mm.

FIG. 4 Walckenaeria dahaituoensis sp. n.; male holotype (A, B, E, F) and female paratype from Dahiatuo N.N.R. (C, D, G). (A) Carapace, frontal view. (B) Same, lateral view. (C) Same, dorsal view. (D) Epigynum, ventral view. (E) Embolic division (with DSA), dorsal view. (F) Same, ventral view (arrow indicating retrolateral groove of supratugulum). (G) Epigynum, posterior view. Scale lines: A-C=0.2 mm, D-G=0.1 mm.

FIG. 5 Walckenaeria dahaituoensis sp. n.; three different female paratypes. (A, C, D) Vulva, ventral view. (B) Same, dorsal view. Scale lines: 0.1 mm.